Mercurial > public > mercurial-scm > hg-stable
diff mercurial/pure/parsers.py @ 46717:913485776542
revlog: introduce v2 format
As documented in [1], this is still tentative and could be subject to change,
but we need to lay down the foundations in order to work on the next abstraction
layers.
[1] https://www.mercurial-scm.org/wiki/RevlogV2Plan
Differential Revision: https://phab.mercurial-scm.org/D9843
| author | Rapha?l Gom?s <rgomes@octobus.net> |
|---|---|
| date | Thu, 28 Jan 2021 15:28:57 +0100 |
| parents | e83327af26f1 |
| children | 502e795b55ac |
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--- a/mercurial/pure/parsers.py Fri Feb 12 16:13:34 2021 -0800 +++ b/mercurial/pure/parsers.py Thu Jan 28 15:28:57 2021 +0100 @@ -233,10 +233,61 @@ return self._offsets[i] -def parse_index2(data, inline): +def parse_index2(data, inline, revlogv2=False): if not inline: - return IndexObject(data), None - return InlinedIndexObject(data, inline), (0, data) + cls = IndexObject2 if revlogv2 else IndexObject + return cls(data), None + cls = InlinedIndexObject2 if revlogv2 else InlinedIndexObject + return cls(data, inline), (0, data) + + +class Index2Mixin(object): + # 6 bytes: offset + # 2 bytes: flags + # 4 bytes: compressed length + # 4 bytes: uncompressed length + # 4 bytes: base rev + # 4 bytes: link rev + # 4 bytes: parent 1 rev + # 4 bytes: parent 2 rev + # 32 bytes: nodeid + # 8 bytes: sidedata offset + # 4 bytes: sidedata compressed length + # 20 bytes: Padding to align to 96 bytes (see RevlogV2Plan wiki page) + index_format = b">Qiiiiii20s12xQi20x" + index_size = struct.calcsize(index_format) + assert index_size == 96, index_size + null_item = (0, 0, 0, -1, -1, -1, -1, nullid, 0, 0) + + +class IndexObject2(Index2Mixin, IndexObject): + pass + + +class InlinedIndexObject2(Index2Mixin, InlinedIndexObject): + def _inline_scan(self, lgt): + sidedata_length_pos = 72 + off = 0 + if lgt is not None: + self._offsets = [0] * lgt + count = 0 + while off <= len(self._data) - self.index_size: + start = off + self.big_int_size + (data_size,) = struct.unpack( + b'>i', + self._data[start : start + self.int_size], + ) + start = off + sidedata_length_pos + (side_data_size,) = struct.unpack( + b'>i', self._data[start : start + self.int_size] + ) + if lgt is not None: + self._offsets[count] = off + count += 1 + off += self.index_size + data_size + side_data_size + if off != len(self._data): + raise ValueError(b"corrupted data") + return count def parse_index_devel_nodemap(data, inline):